High tension submarine cable



Feb. 6, 1934. G. ZAPF 1,945,764

HIGH TENSION SUBMARINE CABLE Filed March 14, 1930 Fig 4.

Y O Q Patented Feb. 6, 1934 1,945,764 men Tension SUBMARINE can Georg Zapi, Cologne, Germany, assignor to Felten & Guilleaume Cariswerk Aotien-Geselisehaft, (Bologne-Mulheim, Germany Application March 14, 1930, Serial No. 435,946, and in Germany March 16, 1929 2 Claims.

It has already been proposed in high tension cables provided with oil impregnated paper insulation to-replace the lead sheathing by bitumen or other similar substance and to avoid the detri- 5 mental effect of the impregnating oil upon the said substitute sheathing by means of a layer of cellulose ether or cellulose ester impermeable to oil and placed between the said sheathing and the paper insulation. However, such a construction of cable is not suitable as a submarine cable owing to the insufficient resistance ofiered by the substances used in substitution for the lead sheathing to the sea-water.

It is more particularly in the case of high voltage cables intended to be used as submarine cables that the substitution of a sheathing of a lighter material is especially desirable owing to the difliculties encountered with the laying of submarine cables.

The present invention relates to a construction of a high tension cable without a lead sheathing, which construction would be capable of being used as a submarine cable owing to the insulating materials which are especially used.

With this object in view, the invention consists in a high tension cable in which a layer of nonmetallic material impermeable to oil, e. g. cellulose ether or cellulose ester, is provided over the oil-impregnated paper insulation and in which a protecting sheathing of a rubber is provided which, for rendering it impermeable and resistant to sea water to a sufficient extent has been freed of water-soluble and water-containing constituents by a long continued washing process and to 5 which water-insoluble and non-hygroscopic filling substances are added, or rubber which, after it has been placed on the conductor, is impregnated with molten paraffin at and in the neighbourhood of the surface for the purpose of closing special treatment during its manufacture, has

been made watertight and resistant to sea-water to a greater extent than a sheathing of ordinary rubber mixtures.

What I claimis:

1. A high tension submarine cable consisting of an oil-impregnated paper insulation provided on the conductor, a non-metallic layer impermeable to oil provided on the said oil-impregnated paper insulation, and a protecting sheathing of a rubber, which has been freed of water-soluble and watercontaining constituents by a long continuous washing process and to which water-insoluble and non-hygroscopic filling substances have been added.

2. A high tension submarine cable consisting of an oil-impregnated paper insulation provided on the conductor, a non-metallic layer impermeable to oil provided on the said oil-impregnated paper insulation, and a protecting sheathing of a rubber, which after it has been laid on the conductor is impregnated with molten paraffin at or in the neighborhood of the surface for the purpose of closing the pores.

GEORG ZAPF. 

